Clamp.



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Patented June 8,1909.

(((nlll GLAMP. APPLICATION FILED N0v.2,19os.

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SAMUEL BLAKE, OF GLIFTONDALE, ltlASSACI-IUSETTS.

CLAMP.

Specification of Letters Patent.

Patented June 8, 1909.

Application filed November 2, 1908. Serial No. 460,663.

To all whom it may coacem:

Be it known that I, SAMUEL BLAKE, of

Cliftondale, in the county of Essex and State B.

of Massachusetts, have invented new and useful Improvements in Clamps,of which the following is a specification.

My invention relates to clamps and the like, and has for its object toprovide an improved portable clamp for holding work and for similaruses. Also it is the object of my invention to provide a clamp of thetype indicated which will be of simple construction, easily manipulatedand powerful in its action.

To these ends my invention consists of a portable clamp, comprising apair of opposed jaws adapted to engage the work to which the clampingpressure is to be applied, a chain or the like connecting the two jaws,and means for taking up, the slack of the chain to force the two jawstogether against the work. The distinguishing feature of my improvedclamp is, therefore, that the two clamping jaws are connected by aflexible chain-like connection, the principal advantages to which arethat the clamp can be applied to' work of curved or other irregularshape, since the flexibility of the chain permits of the latter bendingto conform to the shape of the work. The flexibility of the chainpermits of the clamp being collapsed into small compass when not in use,and a very simple, strong and powerful take-up device may be employed.

Other features of my invention are hereinafter pointed out.

In the accompanying drawings :Figure l is a side elevation of a clampconstructed in accordance with my invention. Fig. 2 is a plan view ofthe clamp shown in Fig. 1. Fig. 3 is a section on line 3-3 of Fig. 2.

Fig. 1 is a section on line 4-4 of Fig. 1. Fig. 5 is a section on line5-5 of Fig. 1. Fig. 6 is described later.

Having reference to the drawings, A and i B are the two jaws of myimproved clamp, l

and C is the chain connecting said jaws. The jaws A and B are hollow,angular castings made, respectively, with arms a and b i to engage theopposite sides of the workl and with perpendicular arms a 12 to rest 1upon the top of the work. The arms a and b may be scored upon their workengagingj faces as shown to prevent slipping.

The chain C extends from jaw A through l sticking of the chain to thesprocket, I make I 1 a perforation b in jaw B, and is locked to thelatter by an arm 6 pivoted at 7) to jaw The free end of arm I)" extendsthrough one of the links of chain C, and said arm is held against theback of jaw B by the strain brought upon the chain when the clamp set asdescribed later. If the jaw A has been first applied to the work, theoperator can grasp the end of chain C adjacent arm Z)" with one hand,and with the other hand shove aw B toward aw A and against the work. Thejaw B is then locked to chain C by re-inserting the free end of lockingarm 6 in one of the links of chain C. The opposite end of chain Cextends through a perroration a 1n aw A and over a sprocket wheel aprovided on a sleeve (4, the latter being fastened by a pin a to a shafta carried by aw A. One end of shaft a is made with an integral ratchetwheel a engaged by a spring pressed detent a pivotally mounted on jaw A.Thus if jaw B has been first applied to one side of the work, theoperator can, by holding the end of chain C adjacent sprocket a with onehand, quickly shove jaw A along chain G into engagement with theopposite side of the work. It will thus be seen that, if either jaw isfirst applied to the work, the other jaw can be quickly adjusted alongchain C to fit the clamp to the work.

The sleeve a is made exterior-1y hexagonal to receive upon it a wrench aby means of which sprocket a can be forcibly rotated in a direction totake up the slack of chain C and thereby draw the two jaws togetheragainst the work with great force after they have been roughly adjustedto fit the work as above described. As the sprocket and its shaft arethus rotated the detent a engaging the teeth of ratchet a holds thesprocket against turning in the opposite direction while the wrench isbeing shifted on sleeve (1.. To unset the clamp the operator, by

' means of wrench a, relieves detent (L7 of the pressure of ratchet aand then lifts said detent out of engagement with ratchet a.

While the sprocket a is being rotated by wrench a and chain C is undertension, the

frictional engagement of the links of said 7 chain with the sprockettends to prevent the teeth of the sprocket from passing out ofengagement with the chain, that is, the chain tends to stick to thesprocket and to wind thereon. Therefore, in order to prevent this 7 thejaw A with a chain deflecting lug a located alongside of sprocket awhich lug guides the chain away from the sprocket after it has passedpartly around the latter.

When my clamp is applied to work which is of such shape that the chaindoes not pass directly from one jaw to the other in a straight lineperpendicular to the work engaging faces of arms (4 b the strain ofchain C sometimes tends to displace or cant the jaws. Therefore, inorder to hold the jaws in proper relation to the work, said jaws areprovided near the outer ends of their arms a and b with adjustable propsor legs a and Z2 respectively. These props are U-shaped pieces embracingchain C, with their legs extending upwardly through slots 0; and 6 inthe jaws. The legs of the props are made with perforations a and 6 andare pivotally and adjustably connected with the jaws by removable pins(4 and 7) extending through the perforations, the slots a and 6 being ofsuliicient length to permit of the props being swung laterally on pins aand 6 as may be required by the shape of the work being clamped. In Fig.6 l have shown my clamp applied to a semicircular piece of work with theprops in operative position holding the work engaging faces of the jawssquarely against the work. As will be observed from this illustration,the w rk is not only subjected to the pressure of the jaws themselves,but the props and the chain also act to force and hold together theparts of the work which they engage.

My improved clamp is of very simple, strong and inexpensiveconstruction, and can be easily and quickly manipulated. Also itspeculiar construction gives it a very wide range of use not only as aclamp but also as a jack. It is however, as a clamp, particularly usefulin boat building laying floors and other situations where strong andpowerful clamp is desired. As a jack it may be employed to lift heavyarticles, to stretch wire fences and the like.

lVhat I claim is 1. A clamp comprising a pair of jaws; a flexibleconnection to which one of said jaws is fixed and means carried by theother jaw and engaging the flexible connection for shifting said jawalong the flexible connection toward the fixed aw to an extent limitedonly by the length of the tlexible connection between the two jaws.

2. A portable clamp comprising a chain; a jaw fixed to said chain; anopposed jaw movably mounted on said chain; a sprocket wheel on themovable jaw and engaging the chain; and means to operate the sprocketwheel to shift the movable jaw on the chain to ard the fixed jaw.

3. A portable clamp comprising a chain; a jaw fixed to said chain anopposed jaw movably mounted on said chain; a sprocket wheel on themovable jaw and engaging the chain; means to operate the sprocket wheelin one direction to shift the movable aw on the chain toward the fixedjaw; and means to hold the sprocket wheel against turning in theopposite direction when the clamp is set.

.1-. A. portable clamp comprising a chain; a jaw fixed to said chain; anopposed jaw 1novably mounted on said chain; a sprocket wheel on themovable aw and engaging the chain; a chain deflector adjacent thesprocket wheel and means to operate the sprocket wheel to shift themovable jaw on the chain toward the fixed jaw.

The above described clamp comprising the angular jaws It and B; thechain C; means on one of the jaws to take up the slack of the chain toset the clamp; and props adjustably mounted on jaws and B, substantiallyas described.

SiUlUEL UTA Ki lV i tnesses ARTHUR l .hxmrm, H. C. Bowsnn.

